Metallic nanowires have served as novel materials for soft electronics due to their outstanding mechanical compliance and electrical properties. However, weak adhesion and low mechanical robustness of nanowire networks to substrates significantly undermine their reliability, necessitating the use of an insulating protective layer, which greatly limits their utility. Herein, we present a versatile and generalized laser-based process that simultaneously achieves strong adhesion and mechanical robustness of nanowire networks on diverse substrates without the need for a protective layer. In this method, the laser-induced photothermal energy at the interface between the nanowire network and the substrate facilitates the interpenetration of the nanowire network and the polymer matrix, resulting in mechanical interlocking through percolation. This mechanism is broadly applicable across different metallic nanowires and thermoplastic substrates, significantly enhancing its universality in diverse applications. Thereby, we demonstrated the mechanical robustness of nanowires in reusable wearable physiological sensors on the skin without compromising the performance of the sensor. Furthermore, enhanced robustness and electrical conductivity by the laser-induced interlocking enables a stable functionalization of conducting polymers in a wet environment, broadening its application into various electrochemical devices.

Conventional thermal management systems contribute significantly to environmental challenges, motivating the exploration of zero-energy techniques such as radiative cooling and solar heating. In this study, an innovative strategy is introduced to transform transparent polydimethylsiloxane into a versatile material via laser-induced pyrolysis. By precisely controlling laser intensity, the material is engineered for multi-thermal management, exhibiting high reflectivity and thermal emission for effective cooling under high-energy processing and strong solar absorption for notable heating under low-energy conditions. Simulation results indicate that applying this material to building roofs could reduce annual energy consumption by up to 26.5%. Moreover, its capability to form Janus structures and all-laser-patterned solar thermoelectric devices highlights its potential for sustainable technologies. This work represents a pioneering strategy in sustainable thermal management for cooling and heating, demonstrating a novel use of a monolith material and a facile fabrication technique and offering a promising solution to global environmental challenges.

Proper customization in size and shape is essential in implantable bioelectronics for stable bio-signal recording. Over the past decades, many researchers have heavily relied on conventional photolithography processes to fabricate implantable bioelectronics. Therefore, they could not avoid the critical limitation of high cost and complex processing steps to optimize bioelectronic devices for target organs with various sizes and shapes. Here, we propose rapid prototyping using all laser processes to fabricate customized bioelectronics. PEDOT:PSS is selectively irradiated by an ultraviolet (UV) pulse laser to form wet-stable conductive hydrogels that can softly interact with biological tissues (50 μm line width). The encapsulation layer is selectively patterned using the same laser source by UV-curing polymer networks (110 μm line width). For high stretchability (over 100%), mesh structures are made by the selective laser cutting process. Our rapid prototyping strategy minimizes the use of high-cost equipment, using only a single UV laser source to process the electrodes, encapsulation, and substrates that constitute bioelectronics without a photomask, enabling the prototyping stretchable microelectrode array with an area of 1 cm2 less than 10 min. We fabricated an optimized stretchable microelectrode array with low impedances (∼1.1 kΩ at 1 kHz) that can effectively record rat's cardiac signals with various health states.

Conductive hydrogels can be used to make electrodes that interface with biological tissues due to their similar mechanical properties and high electrical conductivity in physiological environments. The electrical and mechanical properties of conductive hydrogels have improved in recent years, but they still suffer from poor durability and reliability, particularly in wet environments. Here we show that high-stability conductive hydrogels can be fabricated and adhered to various substrates using laser-induced phase separation and interface structures. With this approach, conducting polymers can be selectively transformed into conductive hydrogels with wet conductivities of 101.4 S cm-1 and patterned with a spatial resolution down to 5 mu m. The conductive hydrogels exhibit high robustness, maintaining their electrochemical properties after 1 h of ultrasonication and 8 months of storage in water. They also exhibit peel and lap-shear strength in wet conditions of 64.4 N m-1 and 62.1 kPa, respectively. We used the conductive hydrogels to make microelectrode arrays that can stably record electrophysiological signals over 3 weeks in rat brains and hearts. The hydrogel electrodes can also be reused through intensive ultrasonication cleaning due to their durability. Robust conductive hydrogels made purely from a conducting polymer can be fabricated using a laser-induced phase separation method that also improves adhesion to a polymer substrate and allows high-resolution selective patterning.

The strategy of obtaining selective electrical properties by laser irradiation of poly(3,4-ethylenedioxythiophene) stabilized with poly(4-styrenesulfonate) (PEDOT:PSS) is breaking new ground in the fabrication process of conductive films. In this study, the theoretical mechanism by which the laser irradiation induces coalescence of PEDOT-rich particles and improves electrical properties of PEDOT:PSS was explored from a thermodynamic perspective. The microstructural evolution by laser irradiation was experimentally verified, and the equivalent environment was implemented from coarse-grained molecular dynamics simulations. The results suggest that selective disruption between pi-pi interactions and electrostatic attraction, the forces governing the PEDOT-rich domain, is a key driving factor for enhanced phase separation in PEDOT:PSS. The energy supplied from the laser provides sufficient molecular mobility to allow the PEDOT-rich core to integrate with other adjacent cores without compromising the strong internal cohesion of its own core. The enhanced mobility leads to bridging-generating events with triggering of active molecular rearrangements between the cores, driving the coalescence of conductive particles.

Soft robots, capable of safe interaction with delicate objects through their flexibility and compliance, are attracting attention in various real-world applications as manipulators, biomedical devices and wearable tools. As these technologies advance, the ability to perform complex tasks in a robust and reliable way becomes essential. Thus, the incorporation of embedded intelligence in soft robots, which enables them to perceive external environments and generate appropriate actions, is increasingly important. Inspiration from sophisticated biological systems, which exhibit optimized behaviours through the acquisition of external information, promotes the development of intelligent soft robots. Here, we introduce biomimicry strategies for intelligent soft robotics and highlight progress in how soft robots interact with their environment and perform tasks. First, we discuss sensors inspired by the sensory nervous systems and soft actuators inspired by the musculoskeletal systems. Furthermore, we investigate various applications such as manipulation, exploration, wearable devices, biomedical devices and imperceptible devices. We conclude discussing the challenges and offering a perspective on the future direction of this field. Soft robots are evolving to perform increasingly complex tasks, with biomimicry having a fundamental role in their development. This Review details biomimetic strategies and pivotal advances in sensors, actuators and applications of intelligent soft robotics.

Liquid crystal elastomers hold promise in various fields due to their reversible transition of mechanical and optical properties across distinct phases. However, the lack of local phase patterning techniques and irreversible phase programming has hindered their broad implementation. Here we introduce laser-induced dynamic crosslinking, which leverages the precision and control offered by laser technology to achieve high-resolution multilevel patterning and transmittance modulation. Incorporation of allyl sulfide groups enables adaptive liquid crystal elastomers that can be reconfigured into desired phases or complex patterns. Laser-induced dynamic crosslinking is compatible with existing processing methods and allows the generation of thermo- and strain-responsive patterns that include isotropic, polydomain and monodomain phases within a single liquid crystal elastomer film. We show temporary information encryption at body temperature, expanding the functionality of liquid crystal elastomer devices in wearable applications.

Photolithography is a well-established fabrication method for realizing multilayer electronic circuits. However, it is challenging to adopt photolithography to fabricate intrinsically stretchable multilayer electronic circuits fully composed of an elastomeric matrix, due to the opacity of thick stretchable nanocomposite conductors. Here, we present photothermal lithography that can pattern elastomeric conductors and via holes using pulsed lasers. The photothermal-patterned stretchable nanocomposite conductor exhibits 3 times higher conductivity (5940 S cm-1) and 5 orders of magnitude lower resistance change (R/R0 = 40) under a 30% strained 5000th cyclic stretch, compared to those of a screen-printed conductor, based on the percolation network formed by spatial heating of the laser. In addition, a 50 μm sized stretchable via holes can be patterned on the passivation without material ablation and electrical degradation of the bottom conductor. By repeatedly patterning the conductor and via holes, highly conductive and durable multilayer circuits can be stacked with layer-by-layer material integration. Finally, a stretchable wireless pressure sensor and passive matrix LED array are demonstrated, thus showing the potential for a stretchable multilayer electronic circuit with durability, high density, and multifunctionality.

Recent advancements in wearable electronics offer seamlessintegrationwith the human body for extracting various biophysical and biochemicalinformation for real-time health monitoring, clinical diagnostics,and augmented reality. Enormous efforts have been dedicated to impartingstretchability/flexibility and softness to electronic devices throughmaterials science and structural modifications that enable stableand comfortable integration of these devices with the curvilinearand soft human body. However, the optical properties of these devicesare still in the early stages of consideration. By incorporating transparency,visual information from interfacing biological systems can be preservedand utilized for comprehensive clinical diagnosis with image analysistechniques. Additionally, transparency provides optical imperceptibility,alleviating reluctance to wear the device on exposed skin. This reviewdiscusses the recent advancement of transparent wearable electronicsin a comprehensive way that includes materials, processing, devices,and applications. Materials for transparent wearable electronics arediscussed regarding their characteristics, synthesis, and engineeringstrategies for property enhancements. We also examine bridging techniquesfor stable integration with the soft human body. Building blocks forwearable electronic systems, including sensors, energy devices, actuators,and displays, are discussed with their mechanisms and performances.Lastly, we summarize the potential applications and conclude withthe remaining challenges and prospects.

The patterning of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) hydrogels with excellent electrical property and spatial resolution is a challenge for bioelectronic applications. However, most PEDOT:PSS hydrogels are fabricated by conventional manufacturing processes such as photolithography, inkjet printing, and screen printing with complex fabrication steps or low spatial resolution. Moreover, the additives used for fabricating PEDOT:PSS hydrogels are mostly cytotoxic, thus requiring days of detoxification. Here, we developed a previously unexplored ultrafast and biocompatible digital patterning process for PEDOT:PSS hydrogel via phase separation induced by a laser. We enhanced the electrical properties and aqueous stability of PEDOT:PSS by selective laser scanning, which allowed the transformation of PEDOT:PSS into water-stable hydrogels. PEDOT:PSS hydrogels showed high electrical conductivity of 670 S/cm with 6-μm resolution in water. Furthermore, electrochemical properties were maintained even after 6 months in a physiological environment. We further demonstrated stable neural signal recording and stimulation with hydrogel electrodes fabricated by laser.

Thanks to spontaneous polarization in molecular structure, piezoelectric polymer, poly(vinylidene fluoride) (PVDF) holds great potential for diverse applications such as organic memory and electromechanical devices. However, the transformation of PVDF into a highly polarized β‐phase has still relied on conventional processes such as repeated mechanical strain, high‐temperature heat treatment, and high‐voltage electric poling, which are time‐consuming and can potentially cause undesired damages. Here, an ultrafast and reversible digital patterning process to transform the polymorphic phase of the PVDF has been developed using the interaction of laser with molecular structure. Plasmonic gold nanoparticles realize the interaction between PVDF and laser by increasing the absorption of the laser and amplifying its characteristics. The parameters of the laser process for phase conversion are designed under the theoretical background based on molecular dynamics (MD) simulation, and through this, the process is able to freely convert phases by simple parameter modifications. The selective laser process enables a monolithically integrated heterogeneous phase of PVDF which is not allowed in conventional single‐phase producing processes. Moreover, a practical soft robot that can control its direction has been developed by utilizing the difference in mechanical responses of each phase to the electric field in a monolithically integrated single functional layer.

Air-breathing engines used in aircraft have a performance limit as the altitude increases, and this determines the service and absolute ceiling altitude. The method of maintaining altitude and speed in a fixed-wing aircraft in level flight using classical control method is generally using thrust for speed increase/deceleration and pitch attitude for altitude increase/decrease. If this method is used near the service ceiling altitude, increasing the pitch to reduce the altitude error results in a speed reduction. Therefore, it is necessary to use a control method that maintains the speed first using the pitch attitude. Especially in the case of unmanned aerial vehicles, these two methods should be automatically available at the right time. In this paper, we propose a method of switching the speed and altitude maintenance algorithm near service ceiling altitude.

Air data systems measure airspeed, pressure altitude, angle of attack and angle of sideslip. These measurements are essential for operating flight control laws to ensure safe flights. Since the loss or corruption of air data measurements is considered as catastrophic, a high level of operational reliability needs to be achieved for air data systems. In the case of unmanned air vehicles, failure of any of air data sensors is more critical due to the absence of onboard pilot decision aid. This paper presents design of a dual redundancy air data system and the integration process for an unmanned air vehicle. The proposed dual-redundant architecture is based on two independent air data probes and redundancy management by central processing in two independent flight control computers. Starting from unit testing of single air data sensor, details are provided of system level tests used to meet overall requirements. Test results from system integration demonstrate the efficiency of the proposed process. Keywords: ëŒ€ê¸°ìžë£Œì‹œìŠ¤í œ, 이중화설계, 체계통합, ëŒ€ê¸°ìžë£Œë³´ì • Keywords: Air Data System, Dual Redundancy Design, System Integration, Air Data Calibration

A photothermal conversion of sol precursor by selective laser sintering (SLS) process has opened a novel patterning way for advanced electronic applications. The SLS process bases on the photo-thermal-chemical effect and features for high precision, fast processing, and room temperature processability without inert gas. Therefore, the effectiveness of the interaction between the nanomaterials and laser has examined on the various conductive metal nanomaterials such as gold, silver, and copper. Although the laser sintering process has shown many achievements on the metal nanomaterials, it has rarely studied for the interaction for the metal oxide nanomaterials. In this study, WOx thin film layer employs the SLS process for post-processing which enables patterning and annealing simultaneously with inducing photochemical redox reaction as well as photothermal effect. The SLS-processed WO3 thin film has shown similar electrochemical performances for the electrochromic application to the thermal annealed WO3 thin film. We have demonstrated a facile and fast fabrication of the electrochromic device (ECD) with the SLS-processed WO3 thin film layer.

In this study, we develop a coarse-to-fine particle filter algorithm for track-before-detect in order to track a subpixel-sized, low signal-to-noise ratio target in sensor data. The proposed algorithm enhances tracking performance in the presence of target motion uncertainty and it also maintains the computational load without increasing the number of particles. This coarse-to-fine particle filter, which is newly applied to track-before-detect, has two recursive stages: a coarse stage for extensive searches of the target’s state space and a fine stage that narrows down the tracking results. During the coarse stage, particles are propagated with uniformly distributed noise to compensate for highly nonlinear target motion. The fine stage disturbs the particles filtered from the coarse stage using Gaussian distributed noise. Monte Carlo simulation results using artificial image sequences indicate improved performance with the proposed algorithm when uncertain large frame-to-frame pixel differences are caused by nonlinear target motions such as jittering effects. The algorithm is also applied to the real camera image frames to verify its detecting performance.

The use of a multi-rotor unmanned air vehicle (UAV) in image acquisition tasks is promising for three-dimensional (3D) object modeling. Such an autonomous data acquisition system can be useful to handle the geometric complexity of objects such as trees and the inherent difficulties of image capture. In this paper, we address the problem of view planning for a camera-equipped multi-rotor UAV to acquire an adequate set of images that leads to more detailed and complete knowledge of the 3D tree model. The proposed algorithm based on shape-from-silhouette methods incorporates both expected new visual information and vehicle movement. Occupancy estimation for volumetric object model serves as a baseline measure of new information. The outlined approach determines next best views across the viewpoint space bounded by the sensor coverage and the capability of the UAV with minimal a priori knowledge of the object. Simulation studies conducted with virtual reality environments show the effectiveness of the algorithm.

This paper presents a modified hidden Markov model (HMM) filtering algorithm for detecting multiple dim targets in image sequence under low SNR condition. The proposed algorithm consists of three steps. As a first step, morphological filtering is applied for extracting features in pre-processing level. The second step is a hidden Markov model filter. To enhance a detecting performance of the filter, state transition probability matrix of HMM filter is updated to the re-defined parameter in each single recursive process. The estimation process uses potential target’s local path from several continuous frames. The last third step is subwindow application. When a target is detected, the target is treated by sub-window to apply individual HMM filtering for detecting multiple targets. Based on numerical results, the proposed algorithm has slightly better detecting performance for multiple targets from a sequence of an image sensor under very low SNR( 2 ; ) conditions

Track-before-detect techniques based on dynamic programming have provided solutions for detecting targets from a sequence of images. In its application to airborne threat detection, dynamic programming solutions should take into account the distinguishable properties of objects in a collision course. This paper describes the development of a new track scoring function that accumulates scores for airborne targets in Bayesian framework. Numerical results show that the proposed scoring function has slightly better detection capabilities.

This paper presents the control of an indoor unmanned aerial vehicle (UAV) using multi-camera visual feedback. For the autonomous flight of the indoor UAV, instead of using onboard sensor informati...